Process of removing sand cores from hollow drill-rod by sand-blast



P. A. E. ARMSTRONG.

PROCESS OF REMOVING SAND comzs FROM HOLLOW DRILL ROD BY SAND BLAST.

Patented Nov. 23, 1920.

APPLICATION FILED DEC. 13, 1919- AME v UR no i ill) - eomparativelyweal: original aliaelroi the .showmg'ilie operation of L .lFio

.llpplieaiioa filed heoember To all wizom may concern:

e ii'slriiown l, l saor El. E. ARM- STRONG, a subject of the liirig ofGreal; Brilain, and a resident of LOHClOIlVlllS, county of Albany, Stateof ear Yorlr, have invents oereain new and iiseful improvements inProcesses of Removing; Sahel Cores from Hollow Drill-Reel Sand-iflasrh,or" "which the following is a s eoiiicaoioia.

invention relaies to a process removing sancl cores from tubularhoclies, such as hollow clrill rocl, loy meansof a sand blast. The termsand eoi used herein eonvenierii expression lo cover sores of variousrefractory ma'ierials such hurried inagiiesihe powder lime. zirconia andthe lilre.

in the man ioiure of tubular horlies such as hollow drill rocl lay hothollow ingot with a sand core therein for elongation and reduction of eoss 'SfiCiZlUl-fi oi ingot and core as by e; 'lhe core iimihe resultins;elongated roci o ecluceel eross section is exizremely romp-ace diflluli; to remove.

lhieretoforaso as l are aware, sueh removal has been accomplished hdrilling}; or by air lolasl. llrillihraoperations are troublesome, slowancl'ezrpensive; While compressed air may he used for this purpose, theclifi'iciiliy with the use of the air hlast, not laden- With abrasiveparticles, resides in the air upon the resistant ('Olfi. Wheii the airor oiher gaseous fluid is laden with abrasive narlicles. making" what isknown as a sand blast this clifii rally is avoioleai. the initial attackis highly powerful anol eil'ective, and the material of the core israpidly hrolren (lown arirl removed.

The accompanying" drawings illustrate apparatus which may be used incarrying out my invention.

in the drawings Figure l is a transverse section of an apparatus inwhich the debris of the core is discharged through the abrasive ladenair enters around 'lhe pipe and between it and ihe hore walls. Fig". 2is an enlarged sectional diagrammaiical View the apparatus of 1., andFig. 3 is a view similar. lo Fig. 2, sea showing ihe'ahrasive laden aireorichieieerhrougl'i the pipe and the discharge takingplace through theannular space between the outside of the pipe and the Walls of the hora.

Refereace numeral 10 oesignales the i; halar hocly suoh rlrill rocl,aiicl. the

sand cleacl at suitable ore a pipe ancisaiicl core which is to heremoved from. the here 12. The hollow heacl 13 is supported in anysuitable manner and ihetuloe 10 is removably olampecl means, such as thecam The pipe estends in'lzo head 13 through packing device as indicatedat 16 in line with ihe here 12; and the pipe 15 is introduced into here12 and advanced therein as the core maierial is removed. Various meansmay he for Sidvaiioirig she pipe 15.

Air unoler pressure is acli ihtecl iao 13 as lay pipe 1? prorirlecl withmeans such as valve 18 to prevent sand from iioiso ifhe air pip Twosources of higher pressure ihari the olher praise ably provided, as. forexample, pipe 19, eeritrollecl val e 20 may carry eompresserl air ssiirefor sand Work a icl pipe 21, also QDHEClZfiCi to piss ii. and cor.-irollecl by valve 2.2 may serve a0 supply roar pressed a higherpressure. lesle'ad or? air other suitable gaseous fluids he ill leansare erovieles for supplying; sire particles. as for example, saricl. tothe ehamher 23 head 13. the form shown. a relatively tall anal narrowcanister 2% is proriolecl communioaiiog with ehamher 23 by passageeonirollecl valve 25. The vanister is preferably macle tell to carry asuiiicienl; quantity of ahrasire. anrl narrow to avoiol undue pressureon the hearl 2", which is preferably bolted in plaee and provided with aplug 27 having a handle 28 for convenieiiee in filling with sam'l time"so time. The pressures are orefe 'ahl v halarieed on opposite sides ovalve 25. as by ihe 'o -i ass pipe 29. controlled by valve 29'. A pine30. controlled by valve 31 is preierah led in about (he top of canisier24.. and serves when desired, to conne i, same to line sour-2e thereinby suitable o shraused; separately when desired... as. for example, iipassage 24 or valve 25 shoizlrl gel". clogged up and require freeing; byarlmirizirig high pressure momentarily behind the semi. As such timespipe 17 is proiecrerl "from sorry of sand, ii the low pressureconnection should he open. hy flap ralveil, and valve 29: may he eioseWhen the air la den with abrasive material 32 is eoriclarierlinto'hihelll aroaiicl the one sicle oi pipe 15, as shown by the arrowsin 1, is is confined so as to exerri its primary attack against the samlcore in a more row annular region algaeeeh lo the here lllll 15, may

walls, as indicated at 33, Figs. 1 and 2. Due to the presence of theabrasive particles the initial attack on the sand core in this region ishighly effective, and the core material being loosened in such annularregion and freed from the bore walls is rapidly broken up and dischargedthrough the bore 34 of pipe 15.

As the sand or other abrasive material 82 may be quite finely divided,no difficulty is encountered in delivering same through the narrowannular passage 35 between pipe 15 and the walls 36 of bore 12, and thepipe be of comparatively large diameter, leaving the bore 34 thereofsufiiciently large for discharge of particles of comparatively largesize, which may result from the effective breaking up of core 11 by thesand blast.

In the alternative apparatus of Fig. 3, the sand blast enters throughthe bore 37 of pipe 38, is discharged centrally against the face of thecore 11, as at 39, and the debris of the .core, together with the sandand air of the sand blast, are discharged through the annular passageabout pipe 38.

The preferred mode of carrying out the invention, however, is as shownin Figs. 1 and 2, since the alternative mode of Fig. 3, while usable,requires a smaller pipe 38 in order to leave sufficient room fordischarge of core particles of even moderate size, and

in the case of making hollow drill having a completed bore of only abouti} of an inch diameter, it is desirable to be able to use a pipe ofmaximum size and ruggedness, also the walls of the drill rod bore arelikely to bemore or less irregular and rough, which also interferes withfree outward passage of comparatively large particles around the pipe38. whereas with theform of Figs. 1 and 2 the particles have a freeoutward passage through the smooth bore 34 of relatively large diameter.Also the form of igs. 1 and 2 is better adapted for removal of hollowcenter cores,- which break down apidly when attacked by sand blast closeup to the bore walls.

To carry out the process the rod containing the core to be removed issecured in lace and the air turned on, preferably the low pressure air.by means of valve 20, the

sand valve 25 being opened sufiiciently to admit the requisite amount ofsand to cham- "or 23 and the removal of the core'is effect- -=l a hasbeen described, the pipe being admasses vanced as needed to keep thesand blast up to its work on the receding faceof the core. If the sandpassage 24 or valve 25 should be clogged, valve 31 can be opened andvalve 29 closed for a short interval, which will usually be all that isnecessary to free the sand passage. If the discharge from the tube 10should become clogged it may be freed by admitting the high pressure airby valve 22, valve 20 being preferably closed at such times.

The discharge can be connected with a source of suction, if desired,though ordinarily this is unnecessary.

It is to be understoodthat the apparatus shown is only for illustrationof apparatus by which the process may be carried into effect, and thatthe process can be carried out by other apparatus than as shown.

I claim:

1. The process of removing sand cores from tubular bodies whichcomprises the steps of introducing a pipe into the bore thereof,delivering air laden with abrasive material against the core through theannular passage between the pipe and the bore walls, and discharging theair and solid particles carried thereby backwardly through the pipe.

2. The process of removing from tubular bodies, such as hollow drillrod, sand cores made hard and compact by elongating and reducing thecross section thereof as by rolling with the sand core in place therein.which comprises the steps of delivering gaseous fluid laden withabrasive material against the sand core, and discharging the material ofthe core backwardly in the opposite direction from that of the fluidentry.

3., ,T he process of removing from tubular bodies. such as hollow drillrod, sand cores ma'de hard and compact by elongating and reducing thecross section thereof as by rolling with the sand core in place therein,which comprises the steps of delivering fluid laden with abrasivematerial against the sand core, discharging the abrasive material andthe material of the sand core backwardly in the opposite direction fromthat of the fluid entry, and advancing the fluid discharge meansprogressively as the core is removed.

In testimony that I claim the'foregoing I hereto set my hand, this 10thday of December, 1919.

rnacr A. E. ARMSTRONG.

